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Effect of the ethanolic extract of Nauclea latifolia (Family: Rubiaceae) on the isolated uterus of non-pregnant rats
Nworgu Z.A.M.,Owolabi O,Atomah J
International Journal of Green Pharmacy , 2010,
Abstract: The plant Nauclea latifolia has been reported to be used by traditional healers to arrest pre-term labour. The ethanolic extract of the root of N. latifolia was screened for activity via agonist-induced contractions of uterine smooth muscles in non-pregnant female albino rats. The extract, at 0.1 and 0.2 mg/ml (final bath concentration), was tested against oxytocin (4×10 -5 to 8×10 -2 I.U/ml: final bath concentration), acetylcholine (0.04 to 40 μg/ml: final bath concentration) and ergometrine (0.05 to 100 μg/ml: final bath concentration) induced contractions invitro. The effect of the extract was compared to that of (0.004 μg/ml: final bath concentration) salbutamol and (0.004 μg/ml: final bath concentration) atropine. Both concentrations of the extract significantly shifted the concentration response curves of oxytocin ( P < 0.01), acetylcholine ( P < 0.0001) and ergometrine ( P < 0.0001) to the right with a slight depression of the Emax. This shift was more with the 0.2 mg/ml concentration, thus suggesting the possibility of a dose dependent action. There was no statistical significant decrease in Emax by 0.1 mg/ml of the extract, while the 0.2 mg/ml produced a significant depression ( P < 0.05) of the Emax, which like salbutamol could not be overwhelmed by higher concentrations of oxytocin. Similarly a significant reduction of the Emax of acetylcholine induced contractions was produced by 0.2 mg/ml, while both concentrations (0.1 and 0.2 mg/ml) produced significant ( P < 0.0001) reduction in Emax of ergometrine. It can thus be concluded that N latifolia root extract reduces oxytocin, acetylcholine and ergometrine-induced uterine contractions. These inhibitions were non-competitive. The result indicates an anti-abortifacient property.
New components of the mercury’s perihelion precession  [PDF]
J. J. Smulsky
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.34034
Abstract: The velocity of perihelion rotation of Mercury's orbit relatively motionless space is computed. It is prove that it coincides with that calculated by the Newtonian interaction of the planets and of the compound model of the Sun’s rotation.
Simple General Purpose Ion Beam Deceleration System Using a Single Electrode Lens  [PDF]
J. Lopes, J. Rocha
World Journal of Engineering and Technology (WJET) , 2015, DOI: 10.4236/wjet.2015.33014
Abstract: Ion beam deceleration properties of a newly developed low-energy ion beam implantation system were studied. The objective of this system was to produce general purpose low-energy (5 to 15 keV) implantations with high current beam of hundreds of μA level, providing the most wide implantation area possible and allowing continuously magnetic scanning of the beam over the sample(s). This paper describes the developed system installed in the high-current ion implanter at the Laboratory of Accelerators and Radiation Technologies of the Nuclear and Technological Cam-pus, Sacavém, Portugal (CTN).
Constraints on velocity anisotropy of spherical systems with separable augmented densities
J. An
Physics , 2011, DOI: 10.1088/0004-637X/736/2/151
Abstract: If the augmented density of a spherical anisotropic system is assumed to be multiplicatively separable to functions of the potential and the radius, the radial function, which can be completely specified by the behavior of the anisotropy parameter alone, also fixes the anisotropic ratios of every higher-order velocity moment. It is inferred from this that the non-negativity of the distribution function necessarily limits the allowed behaviors of the radial function. This restriction is translated into the constraints on the behavior of the anisotropy parameter. We find that not all radial variations of the anisotropy parameter satisfy these constraints and thus that there exist anisotropy profiles that cannot be consistent with any separable augmented density.
On the augmented density of a spherical anisotropic dynamic system
J. An
Physics , 2010, DOI: 10.1111/j.1365-2966.2011.18324.x
Abstract: This paper presents a set of new conditions on the augmented density of a spherical anisotropic system that is necessary for the underlying two-integral phase-space distribution function to be non-negative. In particular, it is shown that the partial derivatives of the Abel transformations of the augmented density must be non-negative. Applied for the separable augmented densities, this recovers the result of van Hese et al. (2011).
Fractional calculus, completely monotonic functions, a generalized Mittag-Leffler function and phase-space consistency of separable augmented densities
J. An
Physics , 2012,
Abstract: Under the separability assumption on the augmented density, a distribution function can be always constructed for a spherical population with the specified density and anisotropy profile. Then, a question arises, under what conditions the distribution constructed as such is non-negative everywhere in the entire accessible subvolume of the phase-space. We rediscover necessary conditions on the augmented density expressed with fractional calculus. The condition on the radius part R(r^2) -- whose logarithmic derivative is the anisotropy parameter -- is equivalent to R(1/w)/w being a completely monotonic function whereas the condition on the potential part is stated as its derivative up to the order not greater than 3/2-b being non-negative (where b is the central limiting value for the anisotropy parameter). We also derive the set of sufficient conditions on the separable augmented density for the non-negativity of the distribution, which generalizes the condition derived for the generalized Cuddeford system by Ciotti & Morganti to arbitrary separable systems. This is applied for the case when the anisotropy is parameterized by a monotonic function of the radius of Baes & Van Hese. The resulting criteria are found based on the complete monotonicity of generalized Mittag-Leffler functions.
When is an axisymmetric potential separable?
J. An
Physics , 2013, DOI: 10.1093/mnras/stt1498
Abstract: An axially symmetric potential psi(R,z)=psi(r,theta) is completely separable if the ratio s:k is constant. Here r*s=d^2(r^2*psi)/dr/d(theta) and k=d^2(psi)/dR/dz. If beta=s/k, then the potential admits an integral of the form of I=(L^2+beta*v_z^2)/2+xi where xi is some function of positions determined by the potential psi. More generally, an axially symmetric potential respects the third axisymmetric integral of motion -- in addition to the classical integrals of the Hamiltonian and the axial component of the angular momentum -- if there exist three real constants a,b,c (not all simultaneously zero, a^2+b^2+c^2>0) such that a*s+b*h+c*k=0 where r*h=d^2(r*psi)/d(sigma)/d(tau) and (sigma,tau) is the parabolic coordinate in the meridional plane such that sigma^2=r+z and tau^2=r-z.
Flaws, Fallacies and Facts: Reviewing the Early History of the Lipid and Diet/Heart Hypotheses  [PDF]
J. Elliott
Food and Nutrition Sciences (FNS) , 2014, DOI: 10.4236/fns.2014.519201
Abstract: The lipid hypothesis of coronary heart disease proposes that a high total cholesterol level has a causative role in coronary heart disease (CHD), specifically in the development of atherosclerosis. It forms the basis for formulating target levels of serum cholesterol and hence the widespread use of statins for lowering cholesterol. An extension of the lipid hypothesis is the diet/heart hypothesis of coronary heart disease. This theory combines two ideas—that saturated fat raises cholesterol levels, and that a reduced saturated fat intake will lower cholesterol levels, thereby inhibiting the development of atherosclerosis and manifestations of CHD. Those who make diet recommendations or prescribe medication to reduce cholesterol may be unaware of the underpinning science. The original research behind these recommendations has given us “healthy heart” guidelines and preventive measures we assume to be true. While the lipid and diet/heart hypotheses are often presented as fact, they remain inadequately proven theories that have little agreement from experts. Historical perspectives can help us understand the basis of current-day beliefs. In the lipid hypothesis case, research from the 1950s and 60s was instrumental in its formation. This early work should not be considered irrelevant, outdated or obsolete because current recommendations from national heart associations in many countries continue to be shaped by these studies. This paper examines evidence used to formulate the lipid hypothesis and, subsequently, the diet/ heart hypothesis. By critically evaluating steps in the formation of the theory, inconsistencies, mistakes and alternate explanations become apparent and cast doubt on its validity.
Influence of Weather Conditions on the Surface Morphology and Wetting Behaviour of Superhydrophobic Quaking Aspen Leaves  [PDF]
J. J. Victor, U. Erb
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.45A010
Abstract:

The effects of different environmental conditions on the wetting properties and surface morphology of surperhydrophobic quaking aspen leaves harvested during the 2011 growth season are examined. During this particular season quaking aspen leaves were not able to retain their superhydrophobic properties and associated surface structure features as they have usually been able to do in other years. Representative scanning electron microscopy images and wetting property measurements of quaking aspen leaf surfaces harvested throughout this season are presented and discussed with the objective of linking weather induced environmental stresses that occurred in 2011 to the sudden and unusual reduction in non-wetting properties and drastic changes in leaf surface structure. Erosion and regeneration rates of leaf wax crystals and the impact that environmental factors can have on these are considered and used to explain the occurrence of these unexpected changes.

Sonographic evaluation of the post-operative rotator cuff: Does tendon thickness matter?  [PDF]
J. Lasbleiz, T. Benkalfate, J. N. Morelli, J. Jan
Open Journal of Clinical Diagnostics (OJCD) , 2013, DOI: 10.4236/ojcd.2013.33015
Abstract: The goal of this work is to determine whether sonographic measures of tendon thickness correlate with post-operative functional parameters or re-tear rates. 53 consecutive patients with supraspinatus tears on MRI were examined by an orthopedic surgeon to determine: pre-and post-operative patient pain (via Constant-Murley scale), night time pain, maximum force production by the affected arm (in pounds), and range of motion deficits. Post-operative ultrasound at 3 and 12 months following surgery was performed to evaluate for recurrent tear and to measure tendon thickness. Post-operative tendon thickness was inversely related to patient age (r = -0.24; p < 0.05). Statistically significantly decreased thickness was observed with Snyder type C lesions (4.2 mm versus 5.1 mm for type A and B; p < 0.05). Tendon thickness decreased post-operatively from 3 to 12 months (r = -0.31; p < 0.05). Only two recurrent tears occurred, preventing statistical assessment of the prognostic value of tendon thickness. Post-operative tendon thickness did not successfully predict post-operative functional outcomes or pain levels (p > 0.05). Normal post-operative tendon thickness of the rotator cuff decreases from 3 to 12 months following surgery. Thickness is reduced in patients with more severe tears and in older patients but does not correlate with post-operative patient pain or functional outcomes.
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